1. Field of the Invention
The present invention relates to a communications network, and in particular to a network in which a party at the edge of the network takes a call and subsequently transfers the call to another party.
2. Related Art
Commonly, service providers in a network such as the PSTN (Public Switched Telephony Network) need to take a call from a calling party, carry out some transaction with the calling party and then route the call to another number. For example, BT operates a service known as ACE which uses a voice recognition platform to provide customers with information relating to their telephone bills. After the customer has received the relevant information, they are offered the option of being connected to a human operator. If the customer takes up this option, the platform then needs to route the call to the appropriate number for the human operator. This operation of taking a call at one number and subsequently routing it to another number is known as take back and transfer. Hitherto, take back and transfer has been implemented using switched-based three party services. The service provider has a switch function within their service platform. This switch function is used to route the incoming call onwards to the new destination. This approach, which is known as tromboning, has a number of disadvantages. One disadvantage is that the called customer is responsible for the payment of the second leg of the call. A further disadvantage is that two circuits in the telecommunications network are tied up for the duration of the call.
According to a first aspect of the present invention, there is provided a method of operating a telecommunications network comprising:
(a) initiating a call from a calling party to a first called party via a network switch;
(b) subsequently releasing a leg of the said call from the network switch to the first called party;
(c) transmitting from the first called party to a network control platform data identifying a second called party;
(d) at the network control platform:
i. correlating the data transmitted in step (c) and the respective call made in step (a).
ii. controlling the network switch to route the call initiated in step (a) to the second called party.
The present invention provides a new way of implementing a take back and transfer function. This is done in such a way that it can be controlled from the edge of the network without requiring any special equipment at the first called party, who typically may be a service provider. The service can be invoked simply using a normal telephone, or, for example, by minor modifications to control scripts running on an IVR (intelligent voice response) platform. At the same time, the method avoids having two circuits tied up simultaneously, and also ensures that the entire cost of the call is billed to the calling party. These advantages are achieved by controlling a network switch to release the leg of the call from the switch to the first called party once the transactions between the calling party and the first called party are completed. Then in a separate communication from the called party to a network control, the first called party communicates the identity of the number to which the call is to be transferred. The network control platform correlates this information with the original call and connects the call through to the final destination.
The information transmitted in step (c) may be communicated to the network control platform via a data communications network. For example, the service provider may have an Internet connection to the service platform and may transfer the necessary data in this way. Preferably however in step (c) the data is transmitted by making a call from the first called party to the network control platform via the telecommunications network. This preferred approach has the advantage that the first called party then needs no additional equipment or interfaces.
Preferably the telecommunications network has an IN (Intelligent Network) architecture, and the network control platform is a service control point.
The present invention is particularly effective when implemented using IN technology. Then the intelligence for the network control platform may be located at one or more service control points which then arm respective switches or service switching points (SSP) to detect the appropriate points in the call.
Preferably in step (a) the call is registered at the network control platform. In this preferred implementation, the call is registered at the outset at the network control platform. The control platform is then primed to detect the release of the call by the first called party, and then to hold, pending receipt of data identifying the second called party, the first leg of the call from the calling party to the network switch.
Preferably on the said leg of the call being released in step (b) the network control platform starts a timer, and the leg of the call from the calling party to the network switch is held until the said timer has expired.
According to a second aspect of the present invention, there is provided a network control platform for use in a method in accordance with the first aspect, the network control platform comprising:
means for registering a call initiated by a calling party via a network switch to a first called party;
a signalling interface for receiving from the first called party data identifying a second called party;
means for correlating the data received from the first called party and a call registered by the said means for registering; and
control means responsive to the said means for correlating and arranged to output a control signal to cause a network switch to switch the call to a second call party.
Preferably the network control platform further comprises means for detecting when a call registered in the means for registering is released by the first called party; and
a timer responsive to the said means for detecting;
in use the network control means holding a leg of a call registered in the means for registering until the said timer has timed out.